JPH01270636A - Method and apparatus for taking sample from flow of bulk solid material - Google Patents

Abstract

PURPOSE: To take out a sample representative of a segment of powdery particle substance flow by sucking a mixture of powdery dust in a delivery hopper and introducing the sucked mixture to the outside and then separating a required fraction of particle using a classifier. CONSTITUTION: An opening 38 is made through the rear wall 22 of a hopper 20 and a flexible pipe 40 is passed through the opening 38. The pipe 40 is coupled with a suction fan 42 which produces a negative pressure for sucking a fine powdery substance produced from a carrying flow 18 through a suction port 90. The substance arrives at a housing 44 and pressed toward the outer sieve face of a hollow sheave 56 and a fluid finer than the mesh of sieve 56 is introduced through the sheave face to piping 54. The piping 54 is coupled with a hollow sheave 86 arranged in a housing 88 and a fluid finer than the mesh of sheave 86 is introduced to piping 89. Consequently, a fraction of particle representative of average fraction (representative of substance in the carrying flow 18) is left and eventually introduced from piping 94 through coupling piping 106 to an analyzer.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention provides a method for determining the main chemical and/or physical characteristic values of a substance to be sampled, in particular a pulverulent material consisting of coal or lignite. When taking a sample from a stream of material, the sample is sampled outside the stream of granular material in the vicinity of the parabolic flow that is formed when the stream of granular material is transferred from an outgoing conveyor belt to another receiving conveyor belt. A sampling method for aspirating in the form of a mixture of dust particles and relatively coarse dust particles and separating from the aspirated mixture the particle fractions required for the analysis of the main characteristic values; This invention relates to a sample collection device for carrying out the test.

[Prior Art] This type of sample collection method and apparatus is used, for example, to qualitatively and quantitatively determine the moisture and/or ash content of coal. However, it is also possible to qualitatively and quantitatively quantify other substances contained in the particulate matter forming the flow. Examples of this include the qualitative and quantitative determination of sulfur content in coal and phosphorus content in iron ore.

No. 1 to Itsu Patent Publication No. 3,616,218 discloses that a sample of a predetermined particle fraction having an average water content that matches the average water content of all particle fractions of the particulate material is taken from a stream of particulate material. , a method and apparatus for determining the moisture content of crude lignite are described. The moisture content of this predetermined particle fraction is used to control the drying process of the particulate material. Dust samples are taken using a suction device equipped with a prefilter and a sieve insert.

DE 2907513 describes a method for sorting materials from coarse to fine particle sizes. In this case, fine dust is obtained when the ore is charged separately, and this dust is used to qualitatively determine the phosphorus content of the ore.
Analyzed for quantification. In order to obtain the required amount of material as a sample, it is possible to suck up some of the dust suspended in the air at the charging station during the charging of the ore. However, it is also possible to obtain this dust by forming it with compressed air or mechanical comminution.

SUMMARY OF THE INVENTION In these two known sample collection methods, at least part of the classifier required for obtaining the particle fraction to be examined is assigned to the suction opening of the suction tube. In this case, the classification device is worn out considerably, causing problems. For example, in mine operations, when the flow rate of granular material to be treated is large, granular material may be present in the suction pipe, especially at the suction port, even if the suction port is located outside the flow of granular material. Collision of the components of the flow is unavoidable, and damage to the classifier and thus disturbance to the operation of the entire system inevitably occurs.

Another difficulty with traditional collection methods is that the particle fraction, which is later utilized to define key chemical and/or physical property values, or the entire material that should correspond to this particle fraction, has its composition. The reason lies in the fact that it does not represent the This lack of agreement is attributed to the fact that the composition of the dust mixture aspirated to make the sample does not correspond to all the compositions of each segment of material of the particulate material that is to be represented by the sample. There are various reasons why a dust mixture becomes aspirated that is not suitable for obtaining a representative sample. That is, part of the dust formed during the transfer of a stream of particulate material from one conveyor belt to another may be carried away by air movement. The movement of the air, e.g. the wind, in this case acts like a kind of separation device, so that dust particles of a given size are carried away, while other dust particles, especially relatively coarse particles, are carried away. It must be taken into consideration that it does not reach the suction pipe by staying at the suction port. Such air movements, especially wind, can vary in strength and direction in an alternating manner, resulting in not only an underrepresentation of a given particle size in the inhaled dust mixture, but also The magnitude of the undesired change in the composition of the dust may also vary, for example, depending on the wind strength.

Another cause of the inadequacy of the amount of dust sucked in for the formation of representative particle fractions lies in the fact that when the air moves, substances from the outside are blown into or introduced into the area of the suction opening. This possibility needs to be taken into account in all mine operations.

It is because the granular materials, e.g. This is because other substances unrelated to the lignite or the granular substances placed on the conveyor belt or substances of a different composition are brought to the suction port. Also, by doing so,
The separated particle fraction necessarily no longer represents the particulate material stream.

The object of the present invention is to ensure that a complete sample collection is carried out despite the presence of unfavorable circumstances and is utilized to define the chemical and/or physical characteristic values separated from the aspirated dust mixture. The object of the present invention is to improve a sampling method and device of the type mentioned at the outset, such that the sample is representative of the particle fraction taken from it or the segment of the particulate material stream from which it is taken. In particular, the characteristic values of the sample may deviate significantly from the corresponding characteristic values of the particulate material stream by making external factors that may cause sample deterioration not act at all or have little effect. This is what we try to avoid.

[Means for Solving the Problem] According to the present invention, this problem is achieved by suctioning the mixture inside a delivery hopper that receives a parabolic flow, leading it out from the delivery hopper via piping, and conducting the analysis there. The problem is solved by separating from the mixture the particle fraction necessary for carrying out the process and directing this particle fraction to a device for determining the main chemical and/or physical characteristic values.

Further, the present invention provides the following as a device for achieving the above-mentioned object. That is, the sample collecting device of the present invention has a suction pipe (40) connectable to a negative pressure generator (42) and a classifier (56, 86), and the classifier separates fine dust particles from relatively coarse particles. The suction port (90) of the suction tube (40) for separating the particle fraction necessary for analyzing the main characteristic values from the suction mixture consisting of dust particles and suctioning the mixture in the vicinity of, and even outside of, the parabolic flow (18) formed when the flow of particulate material is transferred from the delivery conveyor belt to the receiving conveyor belt; The stream (18) is transferred from the delivery conveyor belt 1iIO) to the receiving conveyor belt (16) and inside the transfer hopper (20), outside of said particulate material stream (18), but also in 18
) and the walls of the delivery hopper (20) (22, 23, 24,
26) Insert the suction port (9) of the suction tube (40) between
0), and the classification device is placed outside the delivery hopper (20) in order to separate the particle fraction necessary for analyzing the main characteristic values of the sample.

[Operation and Effect] In the present invention, external factors are almost completely eliminated by performing suction inside the delivery hopper.

As the particulate material stream falls from the outgoing conveyor belt onto the receiving conveyor belt below it, a lot of dust is formed. In contrast to conventional methods, this formed dust is initially retained inside the delivery hopper and a predetermined core fraction of the dust is not carried away by wind or other factors immediately after its formation. On the other hand,
The walls defining the hopper prevent substances from the outside from being introduced into the suction area and causing false results. In addition, the falling of the granular material stream from the outgoing conveyor belt onto the receiving conveyor belt 1 causes supplementary mixing to the extent that the material forming the granular material stream is formed inside the delivery hopper. This contributes to ensuring that almost all areas inside the delivery hopper contain all particle fractions. The same applies if the amount of material being transported is subject to fluctuations. Unless the flow of particulate material stops completely, the amount of dust formed is sufficient to aspirate the sample.

Some of the dust formed is discharged upwards from the delivery hopper, where it is prevented from being carried away by the wind.
stomach. However, this is not related to the desired result of the present invention. This is because the dust mixture aspirated to form the particle fraction to be examined is sucked inside the delivery hopper and thus in areas where separation of the mixture due to wind and other factors cannot occur. .

When applying the sampling method according to the invention, it is easily possible to continuously draw the mixture to the outside. In that case, after separating the particle fraction used to determine the chemical and physical property values, the material stream consisting of this fraction is divided to form individual samples,
Alternatively, it is sometimes necessary to remove excess material that may be present. However, the invention can also be applied if the mixture is drawn in discontinuously, but preferably in stages. In the case of stepwise suction, it is generally the case that a mixture of fine and coarser dust particles is sucked in at regular intervals, preferably with a constant duration of the individual suction steps. Cheating.

It is clear that the larger the number of test sections or segments of the particulate material stream from which the sample is drawn, the more accurate the results will be. For this reason, when discontinuously aspirating the mixture, the aspiration should generally be carried out over at least half of the conveying period, so that at least half of the particulate material stream is taken into account when taking the sample. It is.

It is particularly advantageous to use a flexible, wear-resistant bow to aspirate the mixture in the region between the outer wall of the delivery hopper and the parabolic flow. The end section of a suction tube with a suction opening is impinged by a separate relatively coarse material section, even if it is located outside the falling granular material stream, but the hose is generally elastically deformable. It should be noted that, as a result, it receives almost no mechanical stress. In addition, unavoidable wear can be reduced in an auxiliary manner by making the hose wear-resistant, for example by appropriate selection of the materials.

In the area where the above-mentioned conditions are met, namely the absence of factors that would impermissibly degrade the composition of the sample material, the suction of the suction tube is Where the mouth is placed has no effect on the quality of the result. The suction opening of the suction tube is generally arranged above the central part of the lateral extent of the receiving conveyor belt and, if necessary, advantageously located between the parabolic flow and therefore the falling conveying stream and the outer wall of the transfer hopper. becomes. Additionally, the lower edge of the side wall of the delivery hopper, which is rectangular in cross-sectional shape, is usually arranged so that it is directly above the receiving conveyor belt, and the lower edge of the rear outer wall is adapted, if necessary, to the shape of the trough of the conveyor belt. It is equally advantageous. The front wall of the transfer hopper can be arranged at a relatively large distance from the receiving conveyor belt if necessary to open a path for the stream of granular material to be discharged, which is placed on the conveyor belt. Since it cannot be ruled out that part of the dust mixture forming a vortex inside the transfer hopper is discharged to the outside through this opening, it is necessary to It is recommended that the suction hose inlet be placed between the outer wall of the rear delivery hopper and the parabolic flow.

However, good results can also be obtained if the suction opening is placed in the area between one side wall of the transfer hopper and the parabolic flow. However, it should be avoided to locate the inlet of the suction hose in or near the area of the through hole through which the stream of particulate material on the receiving conveyor belt is conveyed outwardly from the transfer hopper.

During the running of the conveyor belt, vibrations are transmitted to the entire system and thus also to the suction tube, in particular by the conveying stream falling onto the receiving conveyor belt. This is advantageous since it eliminates the risk of blockage of the suction tube.

That is, even if lumps are formed, they do not stick to the interior of the suction tube or suction hose.

This is also the case in particular if the suction tube is not threaded through the wall of the transfer hopper. The boundaries of the recess in the wall for guiding the suction tube should coincide with the outer circumference of the suction tube, so that dust evacuation from the transfer hopper can also be avoided here.

[Example] Embodiments of the present invention are shown in FIGS. 1 and 2. FIG.

In the figure, a conveyed article 12 of particulate material arriving on an outgoing conveyor belt 10 is discharged from the conveyor belt 10 at a reversing drum 14 and is received by a second or receiving conveyor belt 16 . The outgoing conveyor belt 10 and the incoming conveyor belt 16 are arranged essentially perpendicular to each other in the illustrated embodiment. However, the relative placement of these conveyor belts is not critical to the application of the invention.

The conveyed objects 12 discharged from the outgoing conveyor belt 10 fill the gap to the incoming conveyor belt 16 in the form of a falling conveying stream 18 which is essentially a parabolic flow. Reversing drum 1
A delivery hopper 20 is disposed below 4. The delivery hopper 20 has four peripheral wall sections 22, 23, 24.
．． 26, these wall sections define an essentially quadrangular, possibly even approximately square, cross-sectional shape extending from below upwards.

The dimensions of the rear wall portion 22 and the side wall portions 24, 26 of the receiving conveyor belt 16 in the conveying direction 28 are as follows:
These wall portions terminate at their lower ends directly above the conveyor belt 16, thereby forming an upper running zone 30 of the conveyor belt 16 for receiving objects and wall portions 22, 2.
4.26 so that almost no path exists between each lower limit of 4.26. In addition, in the lower region of these wall parts 22, 24.26, fenders in the form of corner pieces 32 made of elastic rubber material are arranged, which corner pieces 32 are connected to the wall parts 22, 24.26. bridging the distance between the lower limit of the conveyor belt 16 or its upper running zone,
It closes any gaps that may occur here.

Only the wall section 23 of the transfer hopper 20 which is forward in the transport direction 28 of the receiving conveyor belt 16 terminates at a distance consisting of the upper running zone 30 of the receiving conveyor belt 16, so that the upper running zone 30 and the lower section of the wall section 23 There is an opening 35 between the edge 34 and the receiving conveyor (16). in the conveying direction 28 while forming a flow (powder material flow 36).
It is scheduled to be transported to

In the illustrated embodiment, the rear wall portion 22 of the transfer hopper 20 is formed with an opening 38 through which a flexible tube or hose 40 is passed and extends into the lower area of the transfer hopper 20. On the one hand, the free end of the hose 40 is held outside the falling conveying stream 18 that falls from the outgoing conveyor belt 10 onto the incoming conveyor belt 16 . On the other hand, by being arranged inside the transfer hopper 20 the suction opening 90 of the flexible hose 40 is present inside the transfer hopper 20 between the falling conveying stream 18 and the rear wall section 22 or is simply It is positioned so that solid matter cannot fall into the suction port 90 solely due to the action of gravity.

A flexible hose 40 (which may have a diameter of 100 mm, for example) is connected via a tube or hose to a suction blower 42 in a manner described below. Suction blower 42
The negative pressure generated by this is used at the suction port of the hose 40 inside the delivery hopper 20.

As long as the objects to be conveyed are conveyed through the delivery conveyor belt 10, swirling dust exists in the entire interior space of the delivery hopper 20, and a part of it is transferred to the delivery hopper due to the negative pressure generated by the suction blower 42. 20 through the suction opening 90 of the hose 40, which passes through the suction opening 90 into the first housing 44, in which an internal chamber is defined by a cylindrical wall. The housing 44 has an opening 48 disposed essentially coaxially with respect to the housing 44.
．． 50 are provided at the lower end and the upper end, respectively, and the opening 48 can be closed by a valve-like member 52. - A pipe 54 is connected to the upper opening 50.

Inside the housing 44, coaxially with the wall of the interior chamber 46, a hollow sheave 561, which is also cylindrical, is arranged, the lower end of which is closed off by a floor 58. In the illustrated example, this floor 58 is not formed as a sheave fabric, but as a board without openings. But is floor 58 necessary? 7 may be formed as a sheave fabric.

The upper end of the hollow sheave 56 is open. Hollow sheave 5
6 is selected to be slightly larger than the diameter of the opening 50, so that the opening 50 is shielded by the hollow sheave 56 from the area of the internal chamber 46 of the housing 44 that is outside the hollow sheave 56. ing.

A rotor 60 is disposed coaxially inside the cylindrical hollow sheave 56, and this rotor is a hollow sheave 56.
162. The hollow shaft 62 is driven by an electric motor 63 via a gear system 64 . The gearing 64 consists of two pulleys 64, 65, the first of which is driven by the electric motor 63. pulley 64
and a pulley 65 seated on the hollow shaft 62-hi of the rotor 60.
The connection is made by a heald 66.

The rotor 60 is basically formed from a U-shaped frame 67.
“1” of this frame is a value slightly smaller than the inner diameter of the hollow sheave 56.On both sides of the hollow shaft 62, the hollow shaft 62
The two frame parts 68,70 extending parallel to the base point and the frame part 72 connecting these frame parts 68.70 with each other and extending orthogonally are formed as tubes. The tubes have openings on the side opposite the hollow shaft 62 from which a stream of compressed air is directed outwardly toward the cylindrical inner surface of the hollow sheave 56. The compressed air is directed and delivered so that the The lower frame part 72 is also provided with nozzle-like openings I] through which compressed air is delivered downwards, ie towards the floor 58 of the hollow sheave 56.

Compressed air is supplied via the hollow shaft 62. Two orthogonal tube sections 74 branch off from this hollow shaft. Each of these sections 74 is connected to a tubing system formed by frame portions 68.70.72. Hollow! 1III62
is connected to a compressed air source 76.

A vibrator 78 is attached to the floor 58 of the hollow sheave 56. The electrical connection leads supplying the energy for operating the vibrator 78 are not shown for reasons of clarity.

Vibrators 78 and connecting leads are well known to those skilled in the art.

The valve-like member 52, which is capable of closing the opening 48 formed in the bottom of the housing 44, is equipped with an actuating device 82 consisting of a piston 84 guided inside a cylinder 83. By correspondingly biasing a piston 84 which is connected to the valve member 52 via a piston rod 85, the valve member 52 can be moved downwardly from the closed position shown, whereby the opening 48 is closed. Dust that is exposed and present in the housing 44 can be exhausted through this opening.

Piping 54 connected to opening 50 in the upper part of housing 44
is connected to a second hollow sheave 86 which is arranged inside a second housing 88 and which is also essentially cylindrical in shape. The inner chamber of the second housing 88 is a pipe 89
The above-mentioned suction blower 42 is connected to the other end of the pipe 89, and this blower supplies the negative pressure necessary for suction of the substance to the hose through the internal chamber of the housing 88, the hose 40, and the pipe 54. 40 at the suction port 90. A separating device in the form of a cyclone is arranged between the housing 88 and the suction blower 42.

A second hollow sheave 86 disposed inside the second housing 88 is connected to a relatively large diameter pipe 94.
Two sheaves 95 and 96 are disposed in the pipe 94, and these sheaves pass through the pipe 94 at right angles, and at that time, they transition so as to be inclined in the direction of the opening 97 formed in the wall of the pipe 94. do.

This opening can be closed by a valve-like member 98, which can be moved between an open position and a closed position by means of an actuating device 99 comprising a cylinder 100 and a piston 102 guided in its interior. .

In the configuration described above, it is ensured that the finely divided material aspirated via the hose 40 forms or contains a particle fraction representative of the segment of the feed material stream from which it originates. Since the suction port 90 faces downward, substances that are not sucked will not reach the hose 40.

Therefore, due to the negative pressure generated by the suction blower 42 and/or the corresponding selection of the suction cross section, the hose 40
The possibility of defining the range of particle sizes to be aspirated via the suction port 90 is obtained. The transfer hopper 20 shields the region from which the material is aspirated from external influences, so that no external influences can act on it, which could significantly degrade the sample taken.

The fine powder substance sucked through the suction port 90 reaches the housing 44, where it is pressed against the outer sheave surface of the cylindrical hollow sheave 56 by the negative pressure generated by the suction blower 42. Particles smaller than the mesh of the sieve pass through the sieve surface of the hollow sieve 56 and reach the pipe 54 from its internal chamber.

A portion of the particles having a diameter larger than the mesh on the sieve surface of the hollow sieve 56 falls downward from the outer surface of the hollow sieve 56 . This is basically the relatively coarse particles of oversized particles and therefore the part of the sucked-in dust that could not pass through the hollow sieve 56. At least some of the relatively fine particles among the large particles are attached to the outer sieve surface of the hollow sieve 56. These particles can be removed by turning on the vibrator 78 at certain times to avoid clogging the sieve. By vibrating in this manner, most of the oversized particles can fall from the hollow sieve 56. If necessary, the sheave surface may be additionally biased from inside by an air stream emitted from the nozzle of the rotor 60. Generally, several revolutions of the rotor 60 are sufficient to clean the sheave. In this case, the negative pressure generated by the suction blower 42 may be reduced during cleaning, but this is not necessary.

Oversized particles collected in the lower region of the housing 44 can be removed through the openings 48 at certain times, with simultaneous actuation of the rotor 60 and removal of the oversized particles from the openings 48. Although it is sometimes useful,
During this period, operation of the suction blower 42 should be interrupted.

The point in time for cleaning the hollow sheave 56 can be determined by measuring the negative pressure behind the hollow sheave 56 in the direction of the air flow. The increase in negative pressure is caused by the hollow sheave 56
This indicates that there is some kind of clogging.

The hybrator turf 8 may be operated continuously in order to pass small diameter particles through the sieve and to clean the dust layer that sometimes settles on the sieve. However, in the case of this mode of operation, in order to retain the suctioned substance on the outer surface of the sieve and to accelerate the passage of small-diameter particles through the sieve by vibration, it is sufficient to generate a stiff vibration. .

Therefore, a separation layer is formed in the housing 44 by the hollow sieve 56, and this separation layer is formed by the second hollow sieve 86.
Specifies the maximum particle size of a finely ladle-shaped solid that reaches . Here, under the action of the negative pressure created by the suction blower 42, the finest particle size fraction is removed, the separation layer being defined by the size of the opening of the hollow sieve 86.

This dust-air mixture containing the finest fraction is first led via line 89 to cyclone 92 where at least most of the solids are removed before passing through air suction blower 42. The solids separated in the cyclone 92 are taken out from the cyclone 92 via a pipe 104.

Therefore, a particle size fraction (particle fraction) representing an average fraction by removing a fraction larger than a predetermined particle size and a fraction smaller than a predetermined particle size reaches the pipe 94 following the second hollow sieve 86 (this The average fraction is representative of the material in the carrier stream from which it was derived). This is therefore the particle size fraction which is referred to as the "main fraction" in DE 36 16 218.

This main fraction must be predetermined by corresponding investigations, and the size of the sieve openings also has to be selected in accordance with the particle size range of the main fraction. The main fraction for this analysis was pipe 9
4 via a connecting pipe 106 to an analytical device (not shown) which is not within the scope of the present invention. Sheaves 95 and 96 arranged in the pipe 94 are used to remove lumps formed while the pipe 54 and the hollow sieve 86 are communicating with each other. This is therefore a safety measure to prevent these lumps from causing disturbance when handling the sample material in the analyzer. To remove these lumps, the valve member 98 is moved to its open position at relatively long intervals. This removal can take place when the valve part 52 associated with the opening 48 in the first housing 44 is in its open position.

The conveyance of the main fraction through the line 106 can also be effected by means of negative pressure, which is applied to the second hollow sheave 8
In order to prevent the classification in step 6 from being disturbed, the negative pressure generated by the suction blower 42 can be synchronized. In this case, the granules conveyed through the line 106 are not turned in the direction of the line 89 in the second housing 38 by the suction action of the suction blower 42 due to their relatively large mass during the corresponding adjustment of the vacuum state. You can take advantage of this situation.

[Brief explanation of the drawing]

FIG. 1 shows a side view of one end of the receiving conveyor I, together with the delivery hopper located above it and the device for separating representative particle fractions; FIG.
It is a front view seen in the direction of arrow I+ in the figure. 10... Sending conveyor belt, 16... Receiving conveyor belt, 20... Delivery hopper, 40... Hose (piping).

Claims (1)

[Claims] 1. When taking a sample from granular material, especially consisting of coal or lignite, in order to later measure the main chemical and/or physical characteristic values of the material to be sampled, The sample is divided into fine dust particles and relatively coarse dust particles from a position outside the flow in the vicinity of the parabolic flow formed when the flow of particulate material is transferred from an outgoing conveyor belt to another receiving conveyor belt. in the form of a mixture of and separating from the aspirated mixture the particle fractions required for carrying out the analysis of the main characteristic values, the mixture being aspirated inside a delivery hopper receiving said parabolic flow. The particle fraction required for the analysis of the main characteristic values is separated from the mixture and is then led out via piping from the delivery hopper to the main chemical and/or physical A sample collection method characterized by guiding the sample to a device that specifies characteristic values. 2. The sample collection method according to claim 1, characterized in that the mixture is continuously aspirated. 3. The sample collection method according to claim 1, characterized in that the mixture is aspirated discontinuously. 4. The sample collection method according to claim 1, wherein the mixture is aspirated in stages. 5. The sample collection method according to claim 4, wherein the mixture is suctioned for at least half of the transportation period. 6. A method according to claim 1, characterized in that the mixture is aspirated using a flexible, wear-resistant hose in the region between the parabolic flow and the defining wall of the transfer hopper. 7. A device for taking samples from a stream of granular material, in particular consisting of coal or lignite, for the subsequent determination of the main chemical and/or physical property values of the material to be sampled, with negative A suction pipe (4) connectable to a pressure generator (42)
0) and a classifier (56, 86), which separates the particle fraction necessary for analyzing the main characteristic values from the suction mixture consisting of fine dust particles and relatively coarse dust particles. and connect the suction opening (90) of the suction tube (40) for suctioning the mixture to the parabolic flow (18) formed when the flow of particulate material is transferred from the outgoing conveyor belt to the incoming conveyor belt. inside a delivery hopper (20) which transfers said stream (18) of particulate material from an outgoing conveyor belt (10) to a receiving conveyor belt (16), in the vicinity of and outside the stream; , the particulate material flow (1
8) and the walls (22, 23, 24, 26) of said particulate material flow (18) and the delivery hopper (20).
) and place the suction port (90) of the suction tube (40) in a position between the transfer hopper and the classification device in order to separate the particle fractions necessary for carrying out the analysis of the main characteristic values of the sample. (20) A sample collection device, characterized in that it is placed outside of the sample collection device. 8. Sampling device according to claim 7, characterized in that the suction tube (40) is formed by a flexible and wear-resistant hose. 9. Sampling device according to claim 7, characterized in that the suction opening (90) of the suction tube (40) is arranged in the center of the transverse extent of the receiving conveyor belt (16). 10. Walls (22, 23, 24) of delivery hopper (20)
, 26), in which the suction tube (40) is guided. 11. Opening in the wall (22) of the delivery hopper (20) (
11. The sample collecting device according to claim 10, characterized in that the boundary of 38) is formed around the suction tube (40).